Friction-testing device.



w. v. TURNER FRlCI ION TESTING DEVICE. APPLICATION FILED DEC. 15. I915.

1 fi fi e Patented Apr. 9,1918.

INVENTOR nnrann snares rnrnnr amen WALTER V. TURNER, F WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE WESTING- HOUSE AIR BRAKE COMPANY, OF WILMERDING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

Specification of Letters Patent.

FRICTION-TESTING Dnvron.

Application filed December 15, 1915. Serial No. 66,992.

Testing Devices, of which the following is a specification. 7

This invention relates to friction testing devices, and the principal object of the invention is to provide improved means for testing the frictional resistance to movement of the moving parts of a triple valve device.

In the accompanying drawing; Figure 1 is a central sectional view of a device embodying my invention applied to a triple valve device, Fig. 2 a rear end elevation thereof; and Fig. 3 a plan view ofthe indicator portion of the testing device.

As shown in the drawings, the testing device may comprise a main casting 1 having base flanges 2 adapted to bear against the bolting flange 3 of the usual triple valve device 4. The casing 1 is provided with a cylindrical bore within which a barrel 5 is slidably mounted. WVithin the outer closed end of the barrel 5 is secured a sleeve 6 containing a stem 7 with the forward end thereof supported by a bearing 8 in the casting 1. A reduced section 9 of the stem 7 extends forwardly for engagement with the piston stem 10 of the triple valve device and a reduced section 11 extends rearwardly and is adapted to engage an indicator 12. A screw 13 in the casting 1 extends into a slot 14 in the barrel 5 for guiding and limiting the movement of the barrel and a coil spring 15 is interposed between the front end wall of the casting 1 and the outer end of the barrel for yieldingly maintaining said barrel in its outward position.

A coil spring 16 is mounted on the portion 11 of the stem between the enlarged section of stem 7 and the end wall of the barrel 5.

The indicator 12 may comprise cylindrical interlocking half sections slidably mounted within the cylindrical bore of an extension 17 of, casting 1 and having interposed springs 18 for pressing the half sections into frictional engagement with the walls of the extension 17.

The half sections are provided with guide pins 19 movable within slots 20 in the extension 17 and adapted to prevent rotative movement of the indicator and one edge of the slot 20 is graduated to show the pounds pressure required to move the triple valve parts.

In operation, the device having been applied to the bolting flange of the triple valve device, as shown in Fig. 1, the barrel 5 is pressed inwardly against the tension of spring 15 and the stem 9, coming in contact with the piston stem 10 of the triple valve device, will be forced outwardly and move the indicator 12 against the tension of the spring 16. When the tension of the spring equals or slightly exceeds the frictional resistance of the triple valve piston and slide valve, the triple valve parts will move and the stem 7 will then return to normal position, but the indicator 12 will remain in the position to which it has been moved and since the graduations on the extension 17 indicate the pounds pressure required to compress the spring 16, the corresponding pressure required to move the triple valve parts will be indicated. If desired, the frictional resistance of the slide valve and the piston can be measured separately by noting the pressure indicated when the piston stem 10 moves but before the slide valve starts to move, which will be the pressure required to move the triple valve piston, and then noting the reading after the slide valve moves. The difference between the first and second readings will be the amount of slide valve friction.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A device for measuring frictional resistance of a mass to movement, comprising a casing adapted to be held stationary, a barrel slidably mounted therein, a spring interposed between the casing and the barrel, 3.

Patented Apr. 9, 1918. i

movable stem for engaging the mass, and a spring interposed between the barrel and the stem.

2. A device for measuring frictional re- 5 sistance of a mass to movement, comprising a casing adapted. to be held stationary, a; barrel'slidably mounted therein, a spring interposeol between the casing and the barrel,

a movable stem for engaging the mass, a movable registering device adapted to be en- 10 gaged by said stem, and a spring interposed between the barrel and the stem.

Inutestimony whereof I have hereunto set my hand.

WALTER v. TURNER.

(Iopiesroflthisapatent maybe ohtaiz'iecl'ifor"fivecentseaeh ny-addressing: the Commissioner-of;Batents,

Washington, D. G. 

